Cycle Question
 

StringerBell wrote on 9/21/2006 8:35 AM:
Thanks for all your advice. The sand in my tank is Carib sea
Agra-Alive---It`s supposed to have bacteria. Should I still get some stuff
from another tank?

The key word is that it's *supposed* to. :-)

Wayne Sallee
Wayne's Pets

Cycle Question
 

StringerBell wrote:
"kim gross" wrote in message
...

Don't do any more water changes. The best thing you could do though is
get a cup or two of sand from another established tank. That will let
you move a good head start of bacteria into your tank and cut the cycle
time way down.


Thanks for all your advice. The sand in my tank is Carib sea
Agra-Alive---It`s supposed to have bacteria. Should I still get some stuff
from another tank?


Yes if you can get some real live sand, that baged live sand is not what
I concider live sand.

Kim

Cycle Question
 

"what is the ED50 for this?"

That's LD50, not ED50. Typo sorry!

Cycle Question
 

"Stoutman" .@. wrote in
m:

I am not sure what you mean by "make it harder", but if you are
implying that high NH3 levels kill the nitrobacter than what is the
ED50 for this? Furthermore, is the ED50 less than the maximum
concentration of NH3 that is normally reached during cycling? Is this
something you found out after doing some research on your own? Heehee
hee heee, snicker! :)

I've heard this claim before--Wayne Sallee did not just pull it out of his
ass through personal or unscientific observation. I believe there is
research out there to back it up.

I am uncertain myself if there is a direct relationship between the levels
of free ammonia and the efficacy of nitric bacterium or an indirect one in
which the relationship is as simple as the fact that the conversion of
nitrite into nitrate requires more oxygen and more energy than the
conversion of ammonia into nitrite and therefore nitrous bacterium have
easier access to available oxygen. Hopefully the previous poster can
produce some referenced material to clear this up.

Btw... according to recently published research done by Tetra the long held
believe that nitrosomonas and nitrobacter are the main bacteria responcible
for the nitrogen cycle in aquaria is false. Tetra research found that
bacteria belonging to completely other sets are doing the bulk of the work,
namely Nitrosococcus and Nitrospira.

Here's a link: http://www.marineland.com/science/nspira.asp

Cycle Question
 

I am not sure what you mean by "make it harder", but if you are
implying that high NH3 levels kill the nitrobacter than what is the
ED50 for this? Furthermore, is the ED50 less than the maximum
concentration of NH3 that is normally reached during cycling? Is this
something you found out after doing some research on your own? Heehee
hee heee, snicker! :)

I've heard this claim before--Wayne Sallee did not just pull it out of his
ass through personal or unscientific observation. I believe there is
research out there to back it up.

Than you must know what he means by "real high ammonia levels makes it
harder on the bacteria"?? I sure don't What do you think he means by "make
it harder"?

I would love to read some literature on this phenomenon.


I am uncertain myself if there is a direct relationship between the levels
of free ammonia and the efficacy of nitric bacterium

I am not aware of any literature that claims that high concentrations of
ammonia (within the realm of a normal cycling) decreases the efficiency of
nitrobacter to metabolise NO2-.

Read the link I provided (first one I came across, I'm sure there are
others) under the heading nitrifying bacteria on the relationship between
NH3 and microbe population. They state (as I have) that the concentration
of the nitrifiers (bacteria) depends on the rate (increased rates yield
increased concentrations) of NH3 production. The faster the rate (and thus
the greater the concentration) the higher the population of both microbes
(nitrobacter and nitrosomonas).

http://www.cci.unl.edu/Teacher/NSF/C...thotrophs.html

or an indirect one in
which the relationship is as simple as the fact that the conversion of
nitrite into nitrate requires more oxygen and more energy than the
conversion of ammonia into nitrite and therefore nitrous bacterium have
easier access to available oxygen.

You are missing the entire point as to why these bacteria are metabolising
NH3 and NO2- in the first place. This process of converting NH3 into NO2-
and NO2- into NO3- does NOT consume energy it PRODUCES energy. This is how
these bacteria produce their metabolic energy (ATP).

I'm not sure which bacteria (nitrobacter or nitrosomona) consume the most
o2.

Hopefully the previous poster can
produce some referenced material to clear this up.

Doubtful

Cycle Question
 

Btw... according to recently published research done by Tetra the long
held
believe that nitrosomonas and nitrobacter are the main bacteria
responcible
for the nitrogen cycle in aquaria is false. Tetra research found that
bacteria belonging to completely other sets are doing the bulk of the
work,
namely Nitrosococcus and Nitrospira.

Here's a link: http://www.marineland.com/science/nspira.asp

Keep reading. I'm willing to bet there findings have a lot to do with there
samples.

read this abstract published in 2005
http://www.ncbi.nlm.nih.gov/entrez/q...ubmed_docsu m

excerpt:
"In the Seine River estuary, especially in the salinity gradient, the
Nitrobacter proportion increases and that of Nitrospira disappears, possibly
due dilution by seawater."

Cycle Question
 

"Stoutman" .@. wrote in :


between NH3 and microbe population. They state (as I have) that the
concentration of the nitrifiers (bacteria) depends on the rate
(increased rates yield increased concentrations) of NH3 production.
The faster the rate (and thus the greater the concentration) the
higher the population of both microbes (nitrobacter and nitrosomonas).

You're incorrectly inferring that a high rate of production means a high
concentration of free NH3. The article is saying that bacteria will
increase their population density in response to an increase in the
availability of their food source. This is natural and to be expected.

Here's the quote:

"The concentration of nitrifiers depends upon the rate of NH3
production in the surrounding environment. The faster the rate, the higher
the population of microbes."

This says nothing about the concentration of measurable NH3 or the effect
the amount of measurable NH3 has on the overall conversion of NH3 into NO3-
in a new system, only that in an established system were the production of
NH3 is high the population of bacteria found using it as a food source will
also be high. In either an established low rate or a high rate environment
the amount of measurable NH3 is likely to be the same, ~0 ppm. We are
talking about fledgling cultures while the article is talking about mature
ones.

Here's another quote for you... I managed to dig it out of an article
published in the Plant and Soil journal in 1972.

"Summary: ...ammonium concentrations in excess of 200 ppm N
reinforced population imbalances conductive to accumulation of nitrite over
time in mixed cultures of Nitrosomonas europaea and Nitrobacter agilis.
Nitrate production proceeded at a low, linear rate characteristic for a
nonproliferating population, indicating a bacteriostatic effect of ammonium
or free ammonia on growth of Nitrobacter rather than an inhibitory effect
on nitrite oxidation."

I guess it is a direct effect after all.



You are missing the entire point as to why these bacteria are
metabolising NH3 and NO2- in the first place. This process of

This point is moot to the topic being discussed.

Either way it was merely a misuse of terms on my part. I fully understand
WHY nitric bacteria do what they do. I was not referring to a greater
demand for metabolic energy. A greater need for resources would have been
a more appropriate term to use in that context.



I'm not sure which bacteria (nitrobacter or nitrosomona) consume the
most o2.

I'm not sure either; it was just a guess or a suggestion at a possible
reason for lack of a documented explanation at the time.



Hopefully the previous poster can
produce some referenced material to clear this up.

Doubtful

What is the point of such a glib attitude in a community where the aim is
the sharing of experience and knowledge?

Is it merely to polish your own ego?

Cycle Question
 

Yep, people tend to think that there is one bacteria that
do this, and one bacteria that do that, but there are many
strains of bacteria on this earth, and I'm sure many
strains not yet discovered. And take plants for example,
think about how many different environments that plants
are able to grow, and many of those plants environments
overlap. I think that to think that this does not happen
with bacteria, is a limiting thought.

As far as high levels of ammonia being hard on the
bacteria that oxidize nitrite into nitrate, it is my
observation over the many years of fish keeping. Naturally
we are talking about real high levels of ammonia here.

Wayne Sallee
Wayne's Pets



dc wrote on 9/21/2006 10:29 PM:
"Stoutman" .@. wrote in
m:

I am not sure what you mean by "make it harder", but if you are
implying that high NH3 levels kill the nitrobacter than what is the
ED50 for this? Furthermore, is the ED50 less than the maximum
concentration of NH3 that is normally reached during cycling? Is this
something you found out after doing some research on your own? Heehee
hee heee, snicker! :)

I've heard this claim before--Wayne Sallee did not just pull it out of his
ass through personal or unscientific observation. I believe there is
research out there to back it up.

I am uncertain myself if there is a direct relationship between the levels
of free ammonia and the efficacy of nitric bacterium or an indirect one in
which the relationship is as simple as the fact that the conversion of
nitrite into nitrate requires more oxygen and more energy than the
conversion of ammonia into nitrite and therefore nitrous bacterium have
easier access to available oxygen. Hopefully the previous poster can
produce some referenced material to clear this up.

Btw... according to recently published research done by Tetra the long held
believe that nitrosomonas and nitrobacter are the main bacteria responcible
for the nitrogen cycle in aquaria is false. Tetra research found that
bacteria belonging to completely other sets are doing the bulk of the work,
namely Nitrosococcus and Nitrospira.

Here's a link: http://www.marineland.com/science/nspira.asp

Cycle Question
 

And if a person does not want to do water changes to
reduce the ammonia levels to keep them from being terribly
hight, I dont' care. It's their rock. They can do what
ever they want to, but if it's my rock, I'm going to keep
the ammonia levels from getting too high, as I want what's
still alive on the rock to remain alive.

Even if it were to cause the cycle to take longer, which I
do not believe, so what. If it's my rock, I want what's
still alive on the rock to stay alive. And I find it odd
when people don't want to try to keep alive what's still
alive on the rock.

Another option is to reduce the needed water changes by
vigorous aeration by using a venturi on the pump. This
helps drive off excess ammonia. It does however have the
downside effect of creating salt creep, and putting more
corrosive salt into the air.

Wayne Sallee
Wayne's Pets

Cycle Question
 

"Stoutman" .@. wrote in
m:

Here's another quote for you... I managed to dig it out of an article
published in the Plant and Soil journal in 1972.

"Summary: ...ammonium concentrations in excess of 200 ppm N
reinforced population imbalances conductive to accumulation of
nitrite over
time in mixed cultures of Nitrosomonas europaea and Nitrobacter
agilis. Nitrate production proceeded at a low, linear rate
characteristic for a nonproliferating population, indicating a
bacteriostatic effect of ammonium
or free ammonia on growth of Nitrobacter rather than an inhibitory
effect on nitrite oxidation."

Just because nitrate production proceeded at a linear rate with
accumulation of nitrite over time does not imply that NH3 production
hinders the ability of nitrobacter to metabolize nitrite.

No it doesn't. What the study found is that the high levels of NH3 do not
hinder the ability of Nitrobacter to oxidize NO2-, but rather it has a
bacteriostatic effect, meaning it inhibits the growth of Nitrobacter in
that environment. The rate of conversation of NH3 into NO2- increased in
the experiment indicating a proliferation of Nitrosomonas in that
environment, however the conversion of NO2- into NO3- proceeded at a linear
rate indicating a nonproliferation of Nitrobacter in that same environment.

They study ran another experiment in which they infused a medium with both
bacterial strains and then enriched each with a graded dose of NH3 and NO2-
in order to populate the medium, after which they increased the
concentration of available NH3 as they did in the previous experiment.
What they found is that the NH3 was converted into NO3- with no measurable
levels of NO2- detected, confirming what was indicated in the previous
study. Established Nitrobacter is able to oxidize its food source
perfectly well in concentrated NH3 environment.


How do they know that the bacteriostatic effect they are describing is
a result of high NH3 concentration? Is this discussed in the
publication or are they making assumptions?

Does the nitrate production proceed at an increased rate as the NH3
concentration drops? This would support their claim.

It was a controlled experiment that took place under laboratory conditions.
The variable in the experiment was the amount of NH3 given to the cultures.
The rate of proliferation of Nitrobacter was found to be directly effected
by the concentration of NH3. So yes, the rate of conversion of NO2- into
NO3- increased in relation to low NH3 concentrations.

You may be able to find the article yourself at a local university library.

Title: Bacteriostatic effect of ammonium on Nitrobacter agilis in mixed
culture with Nitrosomonas europaea
Journal: Plant and Soil
Publisher: Springer Netherlands
Subject: Biomedical and Life Sciences and Earth and Environmental Science
Issue: Volume 36, Numbers 1-3 / February, 1972
Pages 521-527


I am not being glib, but I will admit I come off harsh at times. My
apologies.

Understood, perhaps I judged too quickly. I apologize as well.